Technics RS 1500 Rewind Issue.

[Gary5654]

I have a Technics RS 1500us. Rewind all but stalls out near the end of the Rewind process with 7" and 10.5 Inch. Fast Forward works fine. I've swapped the Supply and Take-Up Reel Tables to see if it's that and to eliminate the Reel Table Board was possibly the issue. No change. I've recapped the Control Board. I do have better adjustment than before but otherwise no change to Rewind. The Tensioner on the Supply side is all the way down when Rewinding and the Tape nears the end. It sits about the middle like the other when Fast Forwarding and during 75 percent of Rewind. The Tape itself becomes really taunt as well. This would seem to indicate too much back tension from the Take-Up side. I have adjusted the Voltages during playback so it's as it should be according to the Manual, but there no adjustment for Rewind or Fast Forward tension so I assume it's adjust via Playback. I have adjusted the Brakes so they are completely clear of the Tables. What am I missing? This is a common problem I'm discovering, but I can't find any information.

 

[phantomrebel]

View attachment 1225425 . I've recapped the Control Board. .

Great deck, I love the 2 I have and use them regularly. Given the known issues with the capacitors in these decks, I would do a full recap as there are several boards that could potentially contribute to this problem (e.g. the power supply board, the reel motor driving board, the reel motor tensioning board, etc..). The motors are electronically controlled so I suspect an electrical issue rather than something mechanical or a simple adjustment.

 

[Tinman]

Well, it's NEVER the tape.... are you SURE you don't have a sticky tape? Even just slightly?
Did you check ALL guides for any deposits? That will slow the deck to a crawl.
Did you check that the 2 top bearings (Tensioners) are rolling smoothly? They often dry up and bind. I always replace them, but you can remove them and use just a little oil
(wipe off well after) JUST TO TEST if the bearing was stiff. They should spin freely.
The bottom roller is generally never a problem, so leave it be.

Lastly, yes... these decks NEED new caps. All the tensions are done by the Reel motor boards on the side. It needs caps regardless, though.

 

[Gary5654]

Well, it's NEVER the tape.... are you SURE you don't have a sticky tape? Even just slightly?
Did you check ALL guides for any deposits? That will slow the deck to a crawl.
Did you check that the 2 top bearings (Tensioners) are rolling smoothly? They often dry up and bind. I always replace them, but you can remove them and use just a little oil
(wipe off well after) JUST TO TEST if the bearing was stiff. They should spin freely.
The bottom roller is generally never a problem, so leave it be.

Lastly, yes... these decks NEED new caps. All the tensions are done by the Reel motor boards on the side. It needs caps regardless, though.

I've use Multiple Tapes to make sure it wasn't the obvious. All Tape guides have been cleaned as have the Heads. In addition the Tape Path has been aligned. The Tension Bearings have been replaced with new ones. I have recapped the Control Board, but not the Reel Table Control Board as I pulled the one from my other Technics 1500-2 Deck which completely works. The same problem still occurs with the Deck I'm trying to fix using the Other's Reel Control Board. There is no problems of any kind during Play or Fast Forward. The Tensioners stay even about 50 percent depressed in both Modes. It's only Rewind which at first seems to be functioning correctly. It's after 3/4 of Rewind you begin to see the Tensioner on the Supply side begin to compresses down and it's completely down about 15 percent short of completely rewinding. You can see the Tape itself starting to show the gap between the Bearing and the outside piece as it's pulling very taught. It never completely stops, but it's all but stopped. As stated above, this does not occur during Fast Forward. To me it says the Back Tension from the Take-up Reel is gradually increasing, which to me implies an Electrical issue. That's why the frustration. This has to be something that has occurred in the past with these Decks, yet for some reason, no information can be found.

 

[stoutblock]

Good luck on the Technics Deck, sorry can’t help you but curious about your Sony TC-880-2 in your aviator? Don’t see those everyday (except I do because I also own one).

 

[Gary5654]

Good luck on the Technics Deck, sorry can’t help you but curious about your Sony TC-880-2 in your aviator? Don’t see those everyday (except I do because I also own one).

I've been a Reel to Reel fan going back to my first purchase of a Deck in 1981. The TC 880 was one of those Dream Decks I always wanted but at the time couldn't afford new, and couldn't find later used. I didn't know until later how few were made. They are suppose to be a culmination of everything Sony learned in building Decks. Being an owner of one now I very much believe that. I ran across the one in the Picture a little while ago on Craigslist. Surprisingly inexpensive. It was still in use by the original owner, and outside of cleaning and having the Bias and general calibration done over time the Unit has never been molested by a Tech. The Sony TC 880 was designed to be a high-end Audiophile Deck and frankly has earned the respect around it.

 

[stoutblock]

I've been a Reel to Reel fan going back to my first purchase of a Deck in 1981. The TC 880 was one of those Dream Decks I always wanted but at the time couldn't afford new, and couldn't find later used. I didn't know until later how few were made. They are suppose to be a culmination of everything Sony learned in building Decks. Being an owner of one now I very much believe that. I ran across the one in the Picture a little while ago on Craigslist. Surprisingly inexpensive. It was still in use by the original owner, and outside of cleaning and having the Bias and general calibration done over time the Unit has never been molested by a Tech. The Sony TC 880 was designed to be a high-end Audiophile Deck and frankly has earned the respect around it.

Agree that it is an awesome deck! Built like a tank at 85 lbs! Mine was a low hour unit when I bought it a few years ago. It is in exceptional condition but did need some internal attention to get it to perform to its full potential. The ribbon cable connectors are known to go brittle and fail and a couple of them had to be rebuilt. All the old grease had gone solid which really cannot be avoided due to age but it all cleaned up very nicely. I've been using it without a single problem for several years now. It does not record nearly at the same caliber as my Sony APR-5003 (few decks do) but it plays back tape very well. Also the coolest meters ever made!

 

[Gary5654]

Agree that it is an awesome deck! Built like a tank at 85 lbs! Mine was a low hour unit when I bought it a few years ago. It is in exceptional condition but did need some internal attention to get it to perform to its full potential. The ribbon cable connectors are known to go brittle and fail and a couple of them had to be rebuilt. All the old grease had gone solid which really cannot be avoided due to age but it all cleaned up very nicely. I've been using it without a single problem for several years now. It does not record nearly at the same caliber as my Sony APR-5003 (few decks do) but it plays back tape very well. Also the coolest meters ever made!

My 880 is calibrated for SM900 and handles it nicely. The 5003 is another I’ll eventually get. I worked with one some years ago and liked it better than Studer. As to playback I favor the sound of the 880. I cleaned up the grease and contacts, but otherwise it was extremely clean and the Ribbon Cable has held up. I don’t think it was in a dry or heated environment ever in its existence. Thanks for the heads up. I’ll watch for the issue, and yes the Meters are very cool.